[BZ #4096]

2007-03-01  Jakub Jelinek  <jakub@redhat.com>
	[BZ #4096]
	* sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Check for NaN
	earlier.
	* math/libm-test.inc (pow_test): Add more tests involving NaNs.

	* sysdeps/i386/fpu/e_powf.S (__ieee754_powf): Avoid invalid exception
	for x qNaN and y either +-inf or non-integer value.
	* sysdeps/i386/fpu/e_pow.S (__ieee754_pow): Likewise.
	* sysdeps/i386/fpu/e_powl.S (__ieee754_powl): Likewise.
	* sysdeps/x86_64/fpu/e_powl.S (__ieee754_powl): Likewise.

5 files changed, 52 insertions, 43 deletions

diff --git a/sysdeps/i386/fpu/e_pow.S b/sysdeps/i386/fpu/e_pow.S
index c554ca4ecb..792f926902 100644
--- a/sysdeps/i386/fpu/e_pow.S
+++ b/sysdeps/i386/fpu/e_pow.S
@@ -1,5 +1,5 @@
 /* ix87 specific implementation of pow function.
-   Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004, 2005
+   Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004, 2005, 2007
    Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
@@ -161,10 +161,11 @@ ENTRY(__ieee754_pow)
 2:	/* y is a real number.  */
 	fxch			// x : y
 	fldl	MO(one)		// 1.0 : x : y
-	fld	%st(1)		// x : 1.0 : x : y
-	fsub	%st(1)		// x-1 : 1.0 : x : y
-	fabs			// |x-1| : 1.0 : x : y
-	fcompl	MO(limit)	// 1.0 : x : y
+	fldl	MO(limit)	// 0.29 : 1.0 : x : y
+	fld	%st(2)		// x : 0.29 : 1.0 : x : y
+	fsub	%st(2)		// x-1 : 0.29 : 1.0 : x : y
+	fabs			// |x-1| : 0.29 : 1.0 : x : y
+	fucompp			// 1.0 : x : y
 	fnstsw
 	fxch			// x : 1.0 : y
 	sahf
@@ -197,9 +198,10 @@ ENTRY(__ieee754_pow)
 	// y == ħinf
 	.align ALIGNARG(4)
 12:	fstp	%st(0)		// pop y
-	fldl	4(%esp)		// x
-	fabs
-	fcompl	MO(one)		// < 1, == 1, or > 1
+	fldl	MO(one)		// 1
+	fldl	4(%esp)		// x : 1
+	fabs			// abs(x) : 1
+	fucompp			// < 1, == 1, or > 1
 	fnstsw
 	andb	$0x45, %ah
 	cmpb	$0x45, %ah
diff --git a/sysdeps/i386/fpu/e_powf.S b/sysdeps/i386/fpu/e_powf.S
index c835b978b9..c91545418d 100644
--- a/sysdeps/i386/fpu/e_powf.S
+++ b/sysdeps/i386/fpu/e_powf.S
@@ -1,5 +1,5 @@
 /* ix87 specific implementation of pow function.
-   Copyright (C) 1996, 1997, 1999, 2001, 2004, 2005
+   Copyright (C) 1996, 1997, 1999, 2001, 2004, 2005, 2007
    Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
@@ -155,10 +155,11 @@ ENTRY(__ieee754_powf)
 2:	/* y is a real number.  */
 	fxch			// x : y
 	fldl	MO(one)		// 1.0 : x : y
-	fld	%st(1)		// x : 1.0 : x : y
-	fsub	%st(1)		// x-1 : 1.0 : x : y
-	fabs			// |x-1| : 1.0 : x : y
-	fcompl	MO(limit)	// 1.0 : x : y
+	fldl	MO(limit)	// 0.29 : 1.0 : x : y
+	fld	%st(2)		// x : 0.29 : 1.0 : x : y
+	fsub	%st(2)		// x-1 : 0.29 : 1.0 : x : y
+	fabs			// |x-1| : 0.29 : 1.0 : x : y
+	fucompp			// 1.0 : x : y
 	fnstsw
 	fxch			// x : 1.0 : y
 	sahf
@@ -191,9 +192,10 @@ ENTRY(__ieee754_powf)
 	// y == ħinf
 	.align ALIGNARG(4)
 12:	fstp	%st(0)		// pop y
-	flds	4(%esp)		// x
-	fabs
-	fcompl	MO(one)		// < 1, == 1, or > 1
+	fldl	MO(one)		// 1
+	flds	4(%esp)		// x : 1
+	fabs			// abs(x) : 1
+	fucompp			// < 1, == 1, or > 1
 	fnstsw
 	andb	$0x45, %ah
 	cmpb	$0x45, %ah
diff --git a/sysdeps/i386/fpu/e_powl.S b/sysdeps/i386/fpu/e_powl.S
index 74f422816a..6215496207 100644
--- a/sysdeps/i386/fpu/e_powl.S
+++ b/sysdeps/i386/fpu/e_powl.S
@@ -1,5 +1,5 @@
 /* ix87 specific implementation of pow function.
-   Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004, 2005
+   Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004, 2005, 2007
    Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
@@ -161,10 +161,11 @@ ENTRY(__ieee754_powl)
 2:	/* y is a real number.  */
 	fxch			// x : y
 	fldl	MO(one)		// 1.0 : x : y
-	fld	%st(1)		// x : 1.0 : x : y
-	fsub	%st(1)		// x-1 : 1.0 : x : y
-	fabs			// |x-1| : 1.0 : x : y
-	fcompl	MO(limit)	// 1.0 : x : y
+	fldl	MO(limit)	// 0.29 : 1.0 : x : y
+	fld	%st(2)		// x : 0.29 : 1.0 : x : y
+	fsub	%st(2)		// x-1 : 0.29 : 1.0 : x : y
+	fabs			// |x-1| : 0.29 : 1.0 : x : y
+	fucompp			// 1.0 : x : y
 	fnstsw
 	fxch			// x : 1.0 : y
 	sahf
@@ -210,9 +211,10 @@ ENTRY(__ieee754_powl)
 	// y == ħinf
 	.align ALIGNARG(4)
 12:	fstp	%st(0)		// pop y
-	fldt	4(%esp)		// x
-	fabs
-	fcompl	MO(one)		// < 1, == 1, or > 1
+	fldl	MO(one)		// 1
+	fldt	4(%esp)		// x : 1
+	fabs			// abs(x) : 1
+	fucompp			// < 1, == 1, or > 1
 	fnstsw
 	andb	$0x45, %ah
 	cmpb	$0x45, %ah
diff --git a/sysdeps/ieee754/dbl-64/e_pow.c b/sysdeps/ieee754/dbl-64/e_pow.c
index d9bd8b479f..1e159f2c0b 100644
--- a/sysdeps/ieee754/dbl-64/e_pow.c
+++ b/sysdeps/ieee754/dbl-64/e_pow.c
@@ -106,20 +106,28 @@ double __ieee754_pow(double x, double y) {
     else
       return y < 0 ? 1.0/ABS(x) : 0.0;                               /* return 0 */
   }
+
+  qx = u.i[HIGH_HALF]&0x7fffffff;  /*   no sign   */
+  qy = v.i[HIGH_HALF]&0x7fffffff;  /*   no sign   */
+
+  if (qx >= 0x7ff00000 && (qx > 0x7ff00000 || u.i[LOW_HALF] != 0)) return NaNQ.x;
+  if (qy >= 0x7ff00000 && (qy > 0x7ff00000 || v.i[LOW_HALF] != 0))
+    return x == 1.0 ? 1.0 : NaNQ.x;
+
   /* if x<0 */
   if (u.i[HIGH_HALF] < 0) {
     k = checkint(y);
     if (k==0) {
-      if ((v.i[HIGH_HALF] & 0x7fffffff) == 0x7ff00000 && v.i[LOW_HALF] == 0) {
+      if (qy == 0x7ff00000) {
 	if (x == -1.0) return 1.0;
 	else if (x > -1.0) return v.i[HIGH_HALF] < 0 ? INF.x : 0.0;
 	else return v.i[HIGH_HALF] < 0 ? 0.0 : INF.x;
       }
-      else if (u.i[HIGH_HALF] == 0xfff00000 && u.i[LOW_HALF] == 0)
+      else if (qx == 0x7ff00000)
 	return y < 0 ? 0.0 : INF.x;
       return NaNQ.x;                              /* y not integer and x<0 */
     }
-    else if (u.i[HIGH_HALF] == 0xfff00000 && u.i[LOW_HALF] == 0)
+    else if (qx == 0x7ff00000)
       {
 	if (k < 0)
 	  return y < 0 ? nZERO.x : nINF.x;
@@ -129,14 +137,6 @@ double __ieee754_pow(double x, double y) {
     return (k==1)?__ieee754_pow(-x,y):-__ieee754_pow(-x,y); /* if y even or odd */
   }
   /* x>0 */
-  qx = u.i[HIGH_HALF]&0x7fffffff;  /*   no sign   */
-  qy = v.i[HIGH_HALF]&0x7fffffff;  /*   no sign   */
-
-  if (qx > 0x7ff00000 || (qx == 0x7ff00000 && u.i[LOW_HALF] != 0)) return NaNQ.x;
-                                                                 /*  if 0<x<2^-0x7fe */
-  if (qy > 0x7ff00000 || (qy == 0x7ff00000 && v.i[LOW_HALF] != 0))
-    return x == 1.0 ? 1.0 : NaNQ.x;
-                                                                 /*  if y<2^-0x7fe   */
 
   if (qx == 0x7ff00000)                              /* x= 2^-0x3ff */
     {if (y == 0) return NaNQ.x;
diff --git a/sysdeps/x86_64/fpu/e_powl.S b/sysdeps/x86_64/fpu/e_powl.S
index 85f4deb3c7..4959bea7ac 100644
--- a/sysdeps/x86_64/fpu/e_powl.S
+++ b/sysdeps/x86_64/fpu/e_powl.S
@@ -1,5 +1,6 @@
 /* ix87 specific implementation of pow function.
-   Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004 Free Software Foundation, Inc.
+   Copyright (C) 1996, 1997, 1998, 1999, 2001, 2004, 2007
+   Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
 
@@ -146,10 +147,11 @@ ENTRY(__ieee754_powl)
 2:	/* y is a real number.  */
 	fxch			// x : y
 	fldl	MO(one)		// 1.0 : x : y
-	fld	%st(1)		// x : 1.0 : x : y
-	fsub	%st(1)		// x-1 : 1.0 : x : y
-	fabs			// |x-1| : 1.0 : x : y
-	fcompl	MO(limit)	// 1.0 : x : y
+	fldl	MO(limit)	// 0.29 : 1.0 : x : y
+	fld	%st(2)		// x : 0.29 : 1.0 : x : y
+	fsub	%st(2)		// x-1 : 0.29 : 1.0 : x : y
+	fabs			// |x-1| : 0.29 : 1.0 : x : y
+	fucompp			// 1.0 : x : y
 	fnstsw
 	fxch			// x : 1.0 : y
 	test	$4500,%eax
@@ -190,9 +192,10 @@ ENTRY(__ieee754_powl)
 	// y == ħinf
 	.align ALIGNARG(4)
 12:	fstp	%st(0)		// pop y
-	fldt	8(%rsp)		// x
-	fabs
-	fcompl	MO(one)		// < 1, == 1, or > 1
+	fldl	MO(one)		// 1
+	fldt	8(%rsp)		// x : 1
+	fabs			// abs(x) : 1
+	fucompp			// < 1, == 1, or > 1
 	fnstsw
 	andb	$0x45, %ah
 	cmpb	$0x45, %ah